1. Field of the Invention
This invention relates to a process for producing lanolin of lower allergen content, non-allergenic lanolin and derivatives thereof.
2. Description of the Prior Art
Lanolin is a higher fatty acid ester with a higher alcohol or sterol. The predominant fatty acid component includes nine chemical forms of normal-, iso- and anteiso-isomers of an alkane acid, and an .alpha.- and .omega.-hydroxy acid. The alcohol component of lanolin includes six chemical forms of normal-, iso- and anteiso-isomers of a mono-alcohol and an .alpha.,.beta.-diol, and several sterols. Lanolin is considered to be a mixture of these alcohols and acids. Additionally, lanolin contains several percent of substances, the structures of which are still unknown. Lanolin is remarkable in that it contains no majority component, though it has a sterol content of about 30%. Thus sterol may be considered to be the main component of lanolin.
Lanolin has hitherto been widely used as a base for drug ointments and for cosmetic creams, lotions and the like. However, lanolin frequently induces allergic reactions at an occurrence frequency ranging from 1 to 18% in patients suffering from dermatitises. Lanolin-induced allergic reactions have been observed with the same or greater frequency as found with allergens such as nickel, chromium, p-phenylenylenediamine and the like, but with less occurrence than with formaldehyde.
The first report on the lanolin-induced allergic reactions, made by Marcus in 1922, was concerned with results obtained with the use of a lanolin alcohol cream as the test compound. In the report, however, no mention was made of what acted as an allergen in the test compound. Thereafter, although many experiments with lanolin were conducted by Sezary et al in 1936, they merely designated a lanolin compound in generalized terminology as an allergen because of the complicated chemical composition of lanolin. Fanburg first estimated lanolin alcohol to be an allergen in 1940, and many studies were then made on lanolin, lanolin alcohol and lanolin derivatives by many researchers over a prolonged period of 30 years. Notwithstanding their energetic efforts, no substances acting as an allergen have been identified to date due to the difficulty of allergy test judgement and the complicated chemical structure of lanolin.